The present invention relates in general to a medical/dental instrument cassette for use in storing and retaining a variety of instruments and equipment used in medical and/or dental procedures. The instrument cassette according to the present invention is suitable for use throughout the washer, decontamination, and sterilization cycle. More specifically, the present invention relates to a medical/dental instrument cassette which is designed with the unique combination of features including a latch design which will not puncture the sterile paper wrapping.
Instrument cassettes which are used for the sterilization of medical and dental instruments and equipment have been designed in a variety of shapes and styles with a variety of features. The following listed patents provide a representative sampling of these earlier designs.
______________________________________ U.S. PATENTS U.S. PAT. NO. PATENTEE ISSUE DATE ______________________________________ 5,279,800 Berry, Jr. Jan. 18, 1994 5,505,916 Berry, Jr. Apr. 4, 1996 4,798,292 Hauze Jan. 17, 1989 4,959,199 Brewer Sep. 25, 1990 5,084,251 Thomas Jan. 28, 1992 4,854,475 Riihimaki et al. Aug. 8, 1989 857,240 Henning Jun. 18, 1907 4,774,063 Runnells Sep. 27, 1988 5,346,677 Risk Sep. 13, 1994 5,215,726 Kudla et al. Jun. 1, 1993 4,930,660 Porteous Jun. 5, 1990 4,541,992 Jerge et al. Sep. 17, 1985 3,285,409 Loran Nov. 15, 1966 5,031,768 Fischer Jul. 16, 1991 4,643,303 Arp et al. Feb. 17, 1987 4,826,348 Brightman May 2, 1989 ______________________________________ FOREIGN PATENTS PAT. NO. COUNTRY DATE ______________________________________ 805,909 Germany Jun. 4, 1951 ______________________________________
When an instrument cassette of the type represented by the listed patents is loaded with instruments and equipment for sterilization, it is important to provide appropriate retainers and storage mechanisms for the items. At the conclusion of the sterilization cycle, the loaded cassette is wrapped with paper as a sterilization wrapping in order to maintain the sterilized condition of the instruments and equipment which have been loaded into the cassette. One of the post-sterilization concerns is maintaining the integrity of the sterilization wrapping. If the wrapping is torn or punctured, atmospheric "dirty" air is able to enter and can contaminate the sterile instruments and equipment. It is therefore important that the cassette be designed without sharp corners and edges and without any protruding portions which could puncture the sterilization wrapping. Part of the concern over punctures is associated with the handling of the cassette. If there is a protruding portion or some sharp edge or corner, such as what might be present with a latch or hinge mechanism, a puncture can occur as the cassette is being wrapped. Even if a puncture does not occur during the wrapping process, a puncture can occur later when the wrapped cassette is handled to place the cassette into storage or remove it from storage. It is conceivable that the individual handling the cassette could grasp it in such a way so as to push the sterilization wrapping inwardly. If this is done in the proximity of a protruding portion, a sharp corner, or a sharp edge, a puncture of the wrapping can occur. As will be appreciated from a review of the listed patents, protruding portions from latches and hinge arrangements are quite common.
It is also important for the lid and tray combination to remain locked together during the washer, decontamination, and sterilization cycle. However, when the loaded cassette is selected for a particular procedure, it is important to be able to separate the lid from the tray with an appropriate breakaway design.
Another concern with the design of medical/dental instrument cassettes is their ability to receive and retain a variety of instruments and equipment. The greater the design versatility and flexibility, the greater the number of procedures which can be accommodated by the cassette design. By arranging the cassette with more "generic" racks, compartments, and holders, the same style of cassette can be used for any one (or more) of several medical and/or dental procedures. For example, the cassette of the present invention can be loaded in one configuration with all of the required instruments and equipment for an endodontic procedure. The same cassette design can also be loaded with a slightly different group of instruments and equipment for a different procedure such as a restorative procedure. Additionally, the cassette of the present invention is equally suitable for a rubber dam procedure.
With the present invention, not only is this design versatility provided, but the present invention incorporates a novel combination of features including a latch design which will not puncture the sterilization wrapping. Notwithstanding the wide variety of earlier cassette designs, the present invention is novel and unobvious.